Surface arthroplasty in shoulder arthritis

Abstract

Use of a resurfacing arthroplasty in shoulder arthritis has the advantage of bone preservation. It diminishes the risk of periprosthetic fractures of the humeral shaft by avoiding the stress concentration effect associated with stemmed implants. Revision or, when rarely needed, arthrodesis may be undertaken more easily since the bone stock has been maintained. The largest studies to date have concluded that the indications for this surface replacement are the same as those for the conventional stemmed prostheses, namely osteoarthritis, rheumatoid arthritis, avascular necrosis, instability arthropathy, posttraumatic arthropathy, and cuff arthropathy. The best results have been achieved in primary osteoarthritis. Results for other indications are comparable with those for stemmed prostheses with a similar follow-up and case mix. Use in cuff tear arthropathy has yielded successful outcomes consistent with the limited goals in these patients, similar to those with use of available stemmed implants but with technical advantages. The implant is not suitable where the humeral head is insufficient or in four-part fractures. In such cases, a stemmed implant should be used. Access to the glenoid is more difficult with this technique because of humeral head retention resulting in a greater propensity to perform hemiarthroplasty.